1. Field of the Invention
The present invention relates to a stream generating apparatus for generating a multiplexed stream including moving picture data, an imaging apparatus having a stream generating function of this type, a data processing apparatus for processing input data including the moving picture data, and a stream generating method. More particularly, the present invention relates to a stream generating apparatus, an imaging apparatus, a data processing apparatus and a stream generating method that all enable processing of moving picture data allowing frame rate switching.
2. Description of Related Art
In recent years, it is generally known to treat a moving picture as digital data, leading to a rapid spread of an imaging apparatus such as a digital video camera that may record an imaged moving picture as the digital data, and a digital recorder that may record a television broadcasting video etc. as the digital data. According to a moving picture compression/encoding scheme used in the apparatus of this type, time control information for playback output and decoding is generally multiplexed and recorded in a data stream together with compressed video data. For MPEG (Moving Picture Experts Group) system, for instance, playback time control information is referred to as PTS (Presentation Time Stamp), and is to be appended to a header of a packet including top data in a decoding/playback unit called an access unit.
By the way, with an advance of imaging device performances and signal processing technologies, the imaging apparatus such as the digital video camera is improved so as to permit the imaged picture to be outputted in a shorter period than a display cycle that meets existing television broadcasting standards, leading to a suggestion of an imaging apparatus provided with such a fast imaging function. For instance, there is one suggestion that specifies an imaging apparatus that enables slow-motion playback by applying a standard or normal frame rate to playback and display of video data provided by being imaged and then recorded at a rate several times faster than the standard frame rate.
As one usual imaging apparatus that allows a playback speed of the moving picture to be varied, it is to be noted that there is provided one technology that assumes use of a counter having an operating speed that is varied at a playback time of a video stream, permitting a count value by the counter to be synchronized with a time stamp appended to the video stream (See Japanese Patent Laid-open 2002-33712 (paragraphs [0020] to [0032] and FIG. 1), for instance).